EP0066151B1 - Système hydraulique de commande avec clapet anti-retour piloté - Google Patents

Système hydraulique de commande avec clapet anti-retour piloté Download PDF

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Publication number
EP0066151B1
EP0066151B1 EP82104214A EP82104214A EP0066151B1 EP 0066151 B1 EP0066151 B1 EP 0066151B1 EP 82104214 A EP82104214 A EP 82104214A EP 82104214 A EP82104214 A EP 82104214A EP 0066151 B1 EP0066151 B1 EP 0066151B1
Authority
EP
European Patent Office
Prior art keywords
actuator
meter
valve
pilot
opening
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired
Application number
EP82104214A
Other languages
German (de)
English (en)
Other versions
EP0066151A3 (en
EP0066151A2 (fr
Inventor
Vinod Kumar Nanda
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Vickers Inc
Original Assignee
Vickers Inc
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Vickers Inc filed Critical Vickers Inc
Publication of EP0066151A2 publication Critical patent/EP0066151A2/fr
Publication of EP0066151A3 publication Critical patent/EP0066151A3/en
Application granted granted Critical
Publication of EP0066151B1 publication Critical patent/EP0066151B1/fr
Expired legal-status Critical Current

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Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B13/00—Details of servomotor systems ; Valves for servomotor systems
    • F15B13/01—Locking-valves or other detent i.e. load-holding devices
    • F15B13/015—Locking-valves or other detent i.e. load-holding devices using an enclosed pilot flow valve

Definitions

  • This invention relates to a hydraulic control system comprising a hydraulic actuator having opposed openings adapted to alternately function as inlets and outlets for moving the element of the actuator in opposite directions, a pump for supplying fluid to said actuator, a pilot operated meter-in valve means to which the fluid from the pump is supplied, a pair of service lines extending from said meter-in valve means to said respective openings or said actuator, a pair of pilot operated meter-out valves, each assigned to one opening of the actuator for controlling the flow out and back to tank, a pilot controller means for alternately supplying fluid at pilot pressure to said meter-in valve means for controlling the position thereof and to that one meter-out valve which receives the flow out of said actuator, so that the meter-in valve means and the meter-out valves are operable for controlling flow to one opening and out of the other opening of the actuator.
  • the present invention is intended particularly to provide a hydraulic system of the above described type which will effectively prevent drift in such applications.
  • the invention comprises the above described hydraulic circuit including at least one check valve operable by said pilot pressure of said controller means for permitting flow from the meter-in valve means to one opening of said actuator, for permitting flow out of said one opening to the assigned meter-out valve and for preventing flow out of said opening in the absence of any pilot pressure, said pilot operated check valve being operable at a.low pilot pressure than said meter-out valve means and including time delay means such that said check valve functions to prevent flow out of said actuator after a predetermined time delay from the time when pilot pressure to said meter-out valve means is interrupted.
  • the hydraulic system embodying the invention comprises an actuator 20, herein shown as a hydraulic cylinder having a rod 21 as the element that is moved in opposite directions by hydraulic fluid supplied from a variable displacement pump 22 which has load sensing control in accordance with conventional construction.
  • the hydraulic system further includes a manually operated controller, not shown, that directs a pilot pressure to a valve system 24 for controlling the direction of movement of the actuator element 21.
  • Fluid from the pump 22 is directed to pump lines 25 and 26 to a meter-in valve means 27 that can comprise one or two spools and functions to direct and control the flow of hydraulic fluid to one (A) or the other opening (B) of the actuator 20.
  • the meter-in valve means 27 is pilot pressure controlled by the controller through pilot control lines 28, 29 and lines 30, 31 to the opposed ends thereof, as presently described. Depending upon the direction of movement of the valve 27, hydraulic fluid passes through service lines 32, 33 to one or the other opening A or B of the actuator 20.
  • the hydraulic system further includes a meter-out valve 34, 35 associated with each end of the actuator in the service lines 32, 33 for controlling the flow of fluid from the end of the actuator to which hydraulic fluid is not flowing from the pump to a tank passage 36, as presently described.
  • the hydraulic system further includes spring loaded poppet valves 37, 38 in the service lines 32,33 and the spring loaded anti-cavitation valves 39, 40 which are adapted to open the lines 32, 33 to the tank passage 36.
  • spring loaded poppet valves are associated with each meter-out valves 34, 35 acting as pilot operated relief valves.
  • a bleed line 47 having an orifice 49 extends from the tank passage 36 to the meter-out valves 34, 35 and to the pilot control lines 28, 29 through check valves 77 in branch lines 28a, 29a.
  • the spring ends of meter-out valves 34, 35 are connected to lines 36, 29a by lines 36a, 29b, respectively.
  • the system also includes a back pressure valve 44 associated with the return or tank line 36.
  • Back pressure valve 44 functions to minimize cavitation when an overrunning or a lowering load tends to drive the actuator down.
  • a charge pump relief valve 45 is provided to take excess fluid above the inlet requirements of the pump 22 and apply it to the back pressure valve 44 to augment the fluid available to the actuator.
  • Meter-in valve 27 comprises a bore in which a spool is positioned. In the absence of pilot pressure, the spool is maintained in a neutral position by springs. The spool normally blocks the flow from the pressure passage 26 to the passages 32, 33. When pilot pressure is applied to either passage 30 or 31, the spool is moved until a force balance exists among the pilot pressure, the spring load and the flow forces. The direction of movement determines which of the service passage 32, 33 is provided with fluid under pressure from passage 26.
  • the same pilot pressure which functions to determine the direction of opening of the meter-in valve also functions to determine and control the opening of the appropriate meter-out valve so that the fluid in the actuator can return to the tank line.
  • pilot pressure is applied to the meter-out valve 34 permitting the flow of fluid out of the opening A of the actuator 20 to the return or tank passage 36.
  • the meter-out valve 34 opens before the meter-in valve 27 can move.
  • the load on the actuator forces hydraulic fluid through the outlet opening A past the meter-out valve 34 to the tank passage 36 which attains a higher pressure than the inlet opening B. Therefore the valve 40 is opened permitting return of some of the fluid to the other end of the actuator 20 through opening B thereby avoiding cavitation.
  • the fluid is shifted between the openings A, B of the actuator and the meter-out valve 34 without opening the meter-in valve 27 and without utilizing fluid from the pump.
  • the controller is bypassed and pilot pressure is applied to both pilot control lines 28, 29.
  • pilot pressure is applied to both pilot control lines 28, 29.
  • This is achieved, for example, by a circuit not shown which will apply the fluid from a pilot pump directly to pilot control lines 28, 29 causing both meter-out valves 34 and 35 to open and thereby permit both ends of the actuator to be connected to tank pressure.
  • the meter-out valve 34, 35 function in a manner permitting fluid to flow back and forth between opposed ends of the cylinder 20.
  • the timing between these valves can be controlled. If the timing is adjusted so that the meter-out valve leads the meter-in valve (as described above), the meter-in valve will control flow and speed in the case where the actuator 20 is being driven by the hydraulic fluid. In the same arrangement with an overhauling load, the load- generated pressure will result in the meter-out valve 34 or 35 controlling flow and speed by throttling action dependent upon the pilot pressure level. In such a situation, the anti-cavitation check valves 39, 40 will permit fluid to flow to the supply side of the actuator so that no pump flow is needed to fill the actuator 20 in an overhauling load mode or condition.
  • a check valve 77 is provided in a branch 28a, 29a of each pilot line 28, 29 adjacent each meter-out valve 34, 35.
  • the valves 77 allow fluid to bleed to passage 36, if there is high pressure due to the above described condition, which fluid is relatively warm, and to circulate through pilot control lines 28, 29 back to the controller and the fluid reservoir when no pilot pressure is applied to the pilot control lines 28, 29.
  • pilot pressure is applied to a pilot control line, the respective check valve 77 closes isolating the pilot pressure from the tank pressure.
  • Each valve system 24 includes a line 79 extending to a shuttle valve 80 that receives load pressure from an adjacent actuator through line 81.
  • Shuttle valve 82 senses which of the pressures is greater and shifts to apply the higher pressure to pump 22.
  • each valve 80, 82 which compare the load pressure therein with the load pressure of an adjacent valve system and transmit the higher pressure to the adjacent valve system in succession and finally apply the highest load pressure to pump 22.
  • a pilot operated check valve 100 is interposed between the opening A or B of the actuator 20 and its respective meter-out valve 34 or 35 which might permit drift by leakage under load, as in the case of an elevated load. If such a condition might occur in either direction, then a pilot operated check valve 100 in accordance with the invention would be utilized with each opening A, B of the actuator.
  • the pilot operated check valve 100 functions to open in response to a lesser pilot pressure than the assigned meter-out valve (here 35) and includes a time delay so that it closes after a predetermined time from the time the pilot pressure to the meter-out valve 35 is removed.
  • pilot operated check valve 100 comprises a body 101 having a port 102 adapted to communicate with service line 33 and a port 103 adapted to communicate with opening B of the actuator 20.
  • Ports 102, 103 extend to a chamber 104 and a check valve member 105 is adapted to open or close communication between ports 102,103.
  • the check valve 100 is similar constructed to a pilot controlled relief valve, that is the movable member 105 of the valve is a differential piston having areas 105a, 105b and 105c which are exposed to pressure in port 102, in port 103 and in a spring chamber 109a, respectively.
  • the valve member 105 includes an axial opening 106 normally closed by a ball 107 which is yieldingly urged into closed position by a guide 108 and a spring 109.
  • a passage 108a equalizes the pressure between opposite sides in guide member 108.
  • a restrictor 105d is arranged between the port 103 and the spring chamber 109a, so that the pressure in port 103 will normally be extended into the spring chamber 109a. Since the area 105c is larger than area 105b, this pressure acts to close the valve member 105. If however the pressure in spring chamber 109a is vented, due to the restrictor 105d the pressure in port 103 for a short time remains high and will move the valve member 105 to the left hand in Fig. 2. Venting is brought by pushing the ball 107 from its valve seat by a pin 110.
  • the pin 110 extends between the chamber 104 and a separate chamber 111 in the body 101 in which a piloting piston 112 is positioned. Chamber 111 communicates with a tank passage in the valve assembly through a port 113.
  • a sealing ring 114 engages pin 110 and hydraulically isolates chambers 104, 111.
  • Piloting piston 112 includes a passage 115 and an orifice 115a providing metered communication between chamber 111 and a piloting chamber 116 thus forming a time delay device.
  • the body 101 includes a pilot pressure port 117 adapted to be connected to the pilot control line 29 in the valve assembly 24 for applying pilot pressure to the valve 100 through an axial passage 118.
  • the passage 118 is normally closed by a ball check valve 119 yieldingly urged against passages 118 by a guide member 120 and a spring 121 in the piloting piston 112.
  • a passage 120a equalizes the pressure between opposite sides of guide member 120.
  • a spring loaded thermal relief valve 122 is provided to relieve excessive hydraulic pressure in the spring chamber 109a as would occur upon expansion due to heating of the fluid beyond a predetermined pressure.
  • the parts and stroke of movements are sized so that the pilot operated check valve 100 will open at a lesser pilot pressure than the meter-out valve 35.
  • pin 110 will push open the valve 107 and so open member 105 before the meter-out valve 35 opens. Therefore, normal flow of the pressure fluid through the passages 103, 102, 33 is possible, as if there were no valve 100. If however the movement of the load has to be stopped, the valve 100 will enter into its proper functioning.
  • pilot pressure is removed from the meter-out valve 35, the orifice 115a and ball check valve 119 function to delay the return movement of the parts 107, 108, 110, so that closing of the member 105 is delayed. Therefore, some position correcting movement of the load is still possible.
  • member 105 finally closes, the load on actuator 20 is locked and prevented from drifting.
  • the check valve 100 is designed with a high pilot ratio (as constituted by the cross sectional area of piloting piston 112 against that of opening 106) so that even a low pilot pressure will open member 105 against the pressure of a high load in actuator 20 and, therefore, also in spring chamber 109a.
  • valve 100 is provided in association with opening A of the actuator.

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  • Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • Fluid Mechanics (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Fluid-Pressure Circuits (AREA)

Claims (7)

1. Un système de commande hydraulique comprenant un dispositif d'actionnement hydraulique (20) comportant des ouvertures opposées (A, B) adaptées pour fonctionner alternativement comme des entrées et des sorties pour déplacer l'élément (21) du dispositif d'actionnement dans des directions opposées, une pompe (22) pour alimenter en fluide ledit dispositif d'actionnement (20), un distributeur de dosage d'entrée actionné par pilote (27) et auquel le fluide débité par la pompe (22) est fourni, deux tuyaux de service (32, 33) s'étendant dudit distributeur de dosage d'entrée (27) jusqu'aux dites ouvertures respectives (A, B) dudit dispositif d'actionnement (20), une paire de distributeurs de dosage de sortie actionnés par pilote (34, 35) et chacun affecté à une ouverture (A, B) du dispositif d'actionnement (20) pour commander l'écoulement sortant et renvoyé au réservoir, une commande-pilote (28, 29) pour fournir alternativement du fluide à une pression-pilote audit distributeur de dosage d'entrée (27) pour commander sa position ainsi qu'à celui des distributeurs de dosage de sortie (34 ou 35) qui reçoit l'écoulement de sortie du dispositif d'actionnement (10), de façon que le distributeur de dosage d'entrée (27) et les distributeurs de dosage de sortie (34, 35) puissent opérer pour commander l'écoulement entrant par une ouverture et sortant par l'autre ouverture du dispositif d'actionnement (20), caractérisé en ce qu'au moins une soupape d'arrêt (100) peut être actionnée par ladite pression-pilote de ladite commande (28, 29) pour permettre un écoulement depuis le distributeur de dosage d'entrée (27) jusqu'à une ouverture (B) dudit dispositif d'actionnement (20), pour permettre un écoulement de sortie de ladite ouverture (B) jusqu'audit distributeur de dosage de sortie affecte (35) et pour empêcher un écoulement à la sortie de ladite ouverture (B) en l'absence d'une pression-pilote, ladite soupape d'arrêt actionnée par pilote (100) pouvant opérer à une pression-pilote inférieure à celle du distributeur de dosage de sortie (35) et comportant des moyens de temporisation (112, 115a, 119) de manière que ladite soupape d'arrêt (100) fonctionne pour empêcher un écoulement à la sortie dudit dispositif d'actionnement (20) au bout d'un temps de retard prédétermine à partir du moment où la pression-pilote appliquée audit distributeur de dosage de sortie (35) est interrompue.
2. Le système hydraulique conforme à la revendication 1, comprenant une soupape d'arrêt actionnée par pilote (100) sensiblement identique et associée à l'autre ouverture (A) dudit dispositif d'actionnement (20) pour commander l'écoulement sortant de ladite autre ouverture (A) dudit dispositif d'actionnement (20).
3. Le système hydraulique selon une quelconque des revendications 1 et 2, dans lequel la soupape d'arrêt (100) comporte un piston différentiel (105) comprenant une première, une seconde et une troisième surface (105a, 105b et 105c), la première surface (105a) étant exposée à la pression régnant dans un tuyau de service (33), la seconde surface (105b) étant exposée à la pression régnant dans ledit dispositif d'actionnement (20) et la troisième surface (105c) étant exposée à la pression régnant dans une chambre à ressort (109a) de ladite soupape d'arrêt (100).
4. Le système hydraulique selon la revendication 3, dans lequel la chambre à ressort (109a) dudit piston différentiel (105) est soumise à la pression régnant dans ledit dispositif d'actionnement (20) par l'intermédiaire d'un étranglement (105d) et peut être déchargée par l'intermédiaire d'un orifice de décharge (106) par un piston actionné par pilote (110, 112).
5. Le système hydraulique selon la revendication 4, dans lequel la section dudit piston (112) est grande par rapport à celle de l'orifice de décharge (106).
6. Le système hydraulique selon la revendication 4 ou 5, dans lequel ledit piston actionné par pilote (110, 112) est soumis à l'influence d'une chambre de pilotage (116) qui est reliée, par l'intermédiaire d'un clapet à bille (119), à ladite commande pilote (29, 117), et par l'intermédiaire d'un passage étranglé (115, 115a) à un passage de réservoir (113).
7. Le système hydraulique selon une quelconque des revendications 1 à 6, dans lequel ladite soupape d'arrêt actionnée par pilote (100) est logée dans un corps unitaire.
EP82104214A 1981-05-28 1982-05-14 Système hydraulique de commande avec clapet anti-retour piloté Expired EP0066151B1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US06/267,853 US4418612A (en) 1981-05-28 1981-05-28 Power transmission
US267853 1981-05-28

Publications (3)

Publication Number Publication Date
EP0066151A2 EP0066151A2 (fr) 1982-12-08
EP0066151A3 EP0066151A3 (en) 1983-10-12
EP0066151B1 true EP0066151B1 (fr) 1986-02-12

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Family Applications (1)

Application Number Title Priority Date Filing Date
EP82104214A Expired EP0066151B1 (fr) 1981-05-28 1982-05-14 Système hydraulique de commande avec clapet anti-retour piloté

Country Status (10)

Country Link
US (1) US4418612A (fr)
EP (1) EP0066151B1 (fr)
JP (1) JPS57200704A (fr)
AU (1) AU552064B2 (fr)
BR (1) BR8203096A (fr)
CA (1) CA1168957A (fr)
DE (1) DE3269048D1 (fr)
IN (1) IN155800B (fr)
MX (1) MX155455A (fr)
NZ (1) NZ200516A (fr)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2005054688A1 (fr) * 2003-12-01 2005-06-16 Norman Ian Mathers Systeme de soupapes pour ensemble a cylindre hydraulique
CN105971965A (zh) * 2016-07-19 2016-09-28 宁波文泽机电技术开发有限公司 流量型平衡阀

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DE3611212C1 (de) * 1986-04-04 1987-06-11 Ernst Dipl-Ing Korthaus Steuerung fuer Hydraulikzylinder als Antriebe fuer Kolbenpumpen
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DE3800188A1 (de) * 1988-01-07 1989-07-20 Danfoss As Hydraulische sicherheitsbremsventilanordnung
US5117935A (en) * 1990-12-21 1992-06-02 Caterpillar Inc. Load sensing hydrostatic steering system
US5331882A (en) * 1993-04-05 1994-07-26 Deere & Company Control valve system with float valve
GB9315778D0 (en) * 1993-07-30 1993-09-15 Pridham Peter W Proportional control hydraulic valves
KR19990087371A (ko) * 1996-02-28 1999-12-27 모서 다니엘 내하중 브레이크 밸브
DE19804398A1 (de) * 1998-02-04 1999-08-05 Linde Ag Ventilanordnung für die Arbeitshydraulik eines Arbeitsfahrzeugs
US6516706B2 (en) * 1999-08-19 2003-02-11 Delaware Capital Formation, Inc. Actuator having internal valve structure
US6282893B1 (en) 1999-08-19 2001-09-04 Delaware Capital Formation, Inc. Self-contained actuator
DE10340504B4 (de) * 2003-09-03 2006-08-24 Sauer-Danfoss Aps Ventilanordnung zur Steuerung eines Hydraulikantriebs
DE10344480B3 (de) * 2003-09-24 2005-06-16 Sauer-Danfoss Aps Hydraulische Ventilanordnung
DE102004025322A1 (de) * 2004-05-19 2005-12-15 Sauer-Danfoss Aps Hydraulische Ventilanordnung
KR100573414B1 (ko) * 2004-07-06 2006-04-26 주식회사 삼천리기계 유압 실린더
US9429174B1 (en) * 2013-03-15 2016-08-30 Clark Equipment Company Enabling valve having separate float and lift down positions
KR20160130390A (ko) * 2014-03-06 2016-11-11 페스토 악티엔 게젤샤프트 운트 코. 카게 밸브 조립체
CN106122142B (zh) * 2016-06-24 2018-08-17 平高集团有限公司 集成式液控单向阀
CN106050780B (zh) * 2016-07-19 2017-10-31 黄培泉 一种流量型平衡阀
CN106704283B (zh) * 2017-02-17 2018-03-20 洛阳理工学院 一种低损耗及减振的先导式顺序阀
JP7211687B2 (ja) 2018-10-17 2023-01-24 キャタピラー エス エー アール エル 降下防止弁装置、ブレード装置および作業機械
CN115013561B (zh) * 2022-08-09 2022-11-11 宁波佳尔灵气动机械有限公司 一种带安全模式的电磁阀

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Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2005054688A1 (fr) * 2003-12-01 2005-06-16 Norman Ian Mathers Systeme de soupapes pour ensemble a cylindre hydraulique
CN105971965A (zh) * 2016-07-19 2016-09-28 宁波文泽机电技术开发有限公司 流量型平衡阀

Also Published As

Publication number Publication date
AU552064B2 (en) 1986-05-22
DE3269048D1 (en) 1986-03-27
EP0066151A3 (en) 1983-10-12
BR8203096A (pt) 1983-06-07
CA1168957A (fr) 1984-06-12
JPS57200704A (en) 1982-12-09
US4418612A (en) 1983-12-06
NZ200516A (en) 1985-03-20
AU8323182A (en) 1982-12-02
MX155455A (es) 1988-03-11
IN155800B (fr) 1985-03-09
JPH0229881B2 (fr) 1990-07-03
EP0066151A2 (fr) 1982-12-08

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